TAMPA, Fla. (AP) — His convention speech finished, Republican Mitt Romney planned to outline a "clear vision of a Romney presidency" in a Thursday night address that's likely to touch on the storm bearing down on the Gulf Coast.

Strategists described the speech in broad terms Tuesday and said they had not discussed contingency plans for changing the timing or content of the prime-time address. Hurricane Isaac was expected to slam the Gulf Coast late Tuesday or early Wednesday.

Romney has largely completed work on the speech after months of preparation, according to senior aide Stuart Stevens, who worked closely with the presidential contender to craft what is likely the most important speech of his political career.

"It'll be a clear vision of a Romney presidency, and very much from his heart about America, and why he wants to be president and what his presidency would be like," Stevens told reporters traveling on the plane that brought Romney and his wife, Ann, to Tampa on Tuesday.

Stevens said the speech, about 40 minutes long, would also include some criticism of President Barack Obama.

"Overwhelmingly, a majority of Americans don't want to vote for this president. You see that over and over and over again," Stevens said. "It's still a choice. There will be an element of that."

Romney and his wife spent much of the weekend rehearsing their speeches near their New Hampshire summer home. Mrs. Romney addresses the convention Tuesday night and her husband will be on hand to watch. Mitt Romney speaks Thursday.

"We're always concerned about people's safety," Ann Romney said when asked about the storm.

Isaac, which delayed the start of the convention by a day, now threatens Louisiana and Alabama as Republicans are set to celebrate Romney's nomination.

Stevens acknowledged that the storm could affect whatever political boost Romney might get from the convention. Candidates typically receive a boost of public support after their party conventions. Polls suggest the race between Obama and Romney is very close.

"This convention's different because of the hurricane," Stevens said, adding that conventions are later in the year than they have been traditionally. "I think if the election were held tomorrow we'd win and win pretty easily."